What does it cost to install a French drain system against my foundation?
If you’re dealing with water pooling near your home or basement moisture problems, a French drain can be an excellent long-term fix. But how much does a French drain cost in Durham, NC? The answer depends on several key factors such as trench depth, soil type, and whether the system is installed inside or outside your foundation.
Below, we break down the main cost factors and typical price ranges so you can estimate what’s realistic for your home.
Main Factors That Affect French Drain Cost
Depth of Trench
Deeper trenches, especially those reaching footings or passing through concrete, require more labor, excavation, and sometimes shoring or concrete removal.
Length of Drain Needed
The longer the drain, the more pipe, gravel, and filter fabric are required, plus extra labor.
Interior vs. Exterior Installation
Interior systems (under basement floors) tend to cost more because of cutting, jackhammering, and concrete restoration. Exterior drains are easier in open soil but trickier in rocky or tight areas, or when landscaping needs to be restored.
Soil Type/Terrain
Clay or rocky soils, high water tables, or restricted access (like crawlspaces) all add complexity and time.
Materials Used
Higher-quality pipe, gravel, or filter fabric, plus extras like catch basins, downspout tie-ins, or sump pumps, raise overall cost but improve longevity
Drainage Outlet / Slope
If gravity drainage is possible, cost stays lower. If a sump pump or extended discharge line is needed, expect higher costs.
Permits & Restoration
Landscaping, concrete, or patios may need to be restored afterward, which can add to final costs.
Typical French Drain Cost per Linear Foot
| Type / Scenario | Average Cost per Linear Foot |
| Exterior shallow drain (yard-level work) | $40–$60/ft |
| Exterior deep or full perimeter foundation drain | $60–$90/ft |
| Interior basement perimeter drain (includes sump pump)** | $60–$90/ft |
For a typical home, that can mean $4,000 to $12,000+ total, depending on layout, soil, and drainage conditions.
Interior vs. Exterior: Which Option Is Best?
- Exterior French drains are best for keeping surface water away from your foundation before it seeps in.
- Interior perimeter drains are ideal if you already have water entering your basement or crawlspace and need to relieve hydrostatic pressure.
A professional inspection can help determine whether you need one or both systems for full waterproofing protection.
French Drain Installation in Durham, NC
Elite Foundation Services offers French drain installation, foundation waterproofing, and drainage solutions across Durham, Chapel Hill, Mebane, and nearby North Carolina communities. Our experienced team provides honest assessments, transparent pricing, and proven waterproofing systems that keep your foundation dry for years to come.
Contact us today for a free estimate on French drain installation or other foundation drainage solutions.
